Advanced Concepts in Water
Smart Landscapes
Day 2: The Finer Points of
Landscape Design
The Team
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Frank Henning, Region IV EPA – CSREES Liaison

Paul. Pugliese, Agriculture & Natural Resources County Extension Agent, University
of Georgia
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Cory Tanner, Urban Horticulture Extension Agent, Clemson Extension
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Tim Davis, Areawide Imported Fire Ant Specialist and Master Gardener Coordinator,
Clemson University
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Eve Brantley, State Water Quality Coordinator Auburn University
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Kerry Smith, Master Gardener Coordinator, Auburn University
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Marco Fonseca, Master Gardener Coordinator, University of Georgia
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Ellen Bauske, Program Coordinator, UGA Center for Urban Agriculture
Funding
The goal of a Water Smart Landscape is
to grow healthy lawn and garden plants
using less water and…
reduce the environmental impact of our
landscapes through sustainable
maintenance practices.
Learning Objectives
a) Common pollution sources in landscape
b) Stormwater runoff collection, water divergence
and on-site treatment
c) Maintain, manage and use irrigation
d) Reduce the impact of common landscape
pollutants
Think Outside the Banks
Off-stream Uses
• Domestic water supply
• Industrial uses
• Agricultural uses
In-Stream Uses
• Maintain healthy biotic systems
• Assimilate pollutants
• Environmental services
• Recreation
Water Use
•
•
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Natural fluctuation of stream flow
Seasonality of outdoor water use
Competition: in-stream vs. off-stream use
Water Smart Landscape Management
Stormwater is ….
Water that does not soak
into the ground
Run-off that can carry
pollutants
Managing Stormwater
Key Concepts Storm Water
Management
1.
2.
3.
4.
Pollution Sources
Infiltration and Impervious Surfaces
Transport & Conveyance
Treatment
Concept #1: Pollution Sources
What’s in your Water?
Trace the Path
Concept #2: Infiltration and
Impervious Surfaces
Impervious Surfaces
Materials like cement, asphalt, roofing, and compacted
soil that prevent percolation of runoff into the
ground.
Inhibits recharge of groundwater
 Prevents natural processing of pollutants in soil & plants
 Provides a surface for accumulation of pollutants
 Provides an express route for pollutants to waterways
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Urban Growth & Impervious
Surfaces
0 – 5%
Natural
0 – 15%
Rural
5 - 65%
Suburban
50 - 95%
Urban
Waterway Health &
Imperviousness
Watershed Imperviousness
0%
10%
Protected
20%
Impacted
30%
40%
Degraded
Waterway Health
Adapted from Schueler, et. al., 1992
50% 60%
Importance of Infiltration
Natural Water Treatment
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Plant Uptake
Soil adsorbtion
Photo-degradation
Drying
Sedimentation
Biochemical/Microbial breakdown
filtration
Concept #3: Transport & Conveyance
(reduce direct connections)
Concept #4 Treatment
(settle, filter, degrade)
Which one do you want in your back
yard?
Forested Riparian Buffer
Hydrology
Flooding and Scouring
Developed
More Runoff
Arriving Faster
Natural
Flooding and Scouring
Water Smart Landscapes
• Reduce sources of pollution
• Increase infiltration
• Enhance treatment/filtration
• Reduce consumption
Non-Point Source Pollution
Non-Point Source Pollution
• Pet Waste
Motor Oil • Cooking Grease
• Metals • Detergents •
Household Hazardous Waste
• Litter
• Yard Waste • Excess
Fertilizer • Pesticides
• Sediment
10 geese defecating during a day of
feeding
123 acre feet @ 200/100mL
Septic System Maintenance
http://www.fcs.uga.edu/ext/pubs/hace/HACE-E-47.pdf
Septic System Maintenance
Grease
Non-Point Source Pollution
Motor Oil • Cooking Grease
• Metals • Pet Waste
• Detergents • Household
Hazardous Waste • Litter
• Yard Waste • Excess
Fertilizer •Pesticides
• Sediment
Fertilizer
More is NOT always better
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Test soil
Excessive growth
Weather conditions
Storm drains, slopes, gutters
Know your plant material
Don’t waste resources
Pesticides
Use IPM
Pesticide Factors
Affecting Water Pollution
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Read the label
Chemical properties of the pesticide
Formulation of the pesticide
Rate and method of application
Pesticide persistence/degradation
Frequency of rainfall; timing of irrigation
Nearness to ponds, rivers, streams, etc
Depth to ground water
Protecting Water from Pesticides
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Read the label
Follow all label instructions
Calibrate all application equipment
Apply at proper rates and times as per label
Store and dispose of pesticides properly
If you have options, choose the least toxic
pesticide
Non-Point Source Pollution
Motor Oil • Cooking Grease
• Metals • Pet Waste
• Detergents • Household
Hazardous Waste • Litter
• Yard Waste • Excess
Fertilizer •Pesticides
• Sediment
Erosion & Sedimentation
Stages in Erosion &
Sedimentation
1. Detachment
2. Transport
3. Deposition
TYPES OF WATER EROSION
SPLASH
Insert picture here
SHEET
RILL &
GULLY
STREAM &
CHANNEL
Questions?
Take a 10 minute break
Managing the Landscape
Water Smart Landscapes
• Reduce sources of pollution
• Increase infiltration
• Enhance treatment/filtration
• Reduce consumption
Avoid Bare Soil
Benefits of Vegetation
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Absorbs raindrop impact
Reduces detachment
Roots hold soil in place
Slows water flow
Adds organic material to the soil
Reduces runoff
Increases infiltration
Mulch &
Organic material
LONG STEEP SLOPES
Photograph of a slope
Minimize Impervious Footprint
Porous Surfaces
Home Landscape Stormwater
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The traditional approach
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Collect, Concentrate, Convey
Better Site Design Practices
Connected
Disconnected
(increases stormwater)
(decreases stormwater)
Dry Well
On-site vs. Regional Approaches
On-site: Manage
stormwater as close
to the source as
possible
Regional: Rely on
large, regional
detention facilities
Disconnect
Impervious Areas
From Streams
What is a
Rain Garden?
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A constructed depression that captures a shallow
amount of water and holds it for a short time period
Runoff is captured and infiltrates into the soil in
where plants and soils utilize and filter the water
It’s also a garden!
Purpose of a Rain Garden
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Captures runoff
from impervious
areas such as roofs,
driveways, patios
Reduce runoff
leaving the site
Important to catch
the first inch of
rainfall
How Rain Gardens Work
Benefits of Rain Gardens
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Lower water use and a beautiful landscape feature
Increases infiltration in landscapes with
impervious surfaces
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infiltrates more water than a flat or sloped lawn area
Reduces flooding risks
and stream bed destruction
downstream
Can provide a new kind of
habitat in the landscape
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Planning Your Rain Garden
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Location
Size
Installation
Plant selection
Locating a Rain Garden in Landscapes
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10 ft from a building foundation
25 feet from septic system drainfield
25 feet from well head
Natural water movement
Aesthetics
Locations to AVOID
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Where water stands for long periods
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Poorly drained soil
Slopes greater 12%
Over utilities
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Water should drain within 48-72 hours
Call before you dig - 811
Inside the dripline of any valued
trees
Problem Soils
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Do a perk test
 Dig 6-8” wide & deep hole
 Fill once and drain
 Fill again & time it
 Should drain in 12 hours
Rain Garden Sizing
Soil
type
Impervious drainage area
Pervious drainage area
Calculating Rain Garden Size
20
20’
20’
50’
15’
15’
1. Define drainage area
2. Determine soil type: sandy, loamy, clayey
3. Calculate rain garden size:
Sandy soil = Drainage area * 0.05 to 0.07
Loamy soil = Drainage area * .0.07 to 0.10
Clayey soil = Drainage area * 0.10 to 0.15
20’
Sample Calculation 2000 sq ft
Drainage Area
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Heavy Clay Soil
2000 sq. ft. x 0.15 =
300 sq. ft.
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Sandy Soil
2000 sq. ft. x 0.05 =
100 sq. ft.
Size and Shape
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Rain gardens are usually not square or a perfect
circle
The longest dimension should be perpendicular
to the major slope
The shorter length should go down the major
slope
Installing the Rain Garden
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Layout edge with rope or garden hose
Call before you dig – 811
Stockpile topsoil
Use subsoil to create a berm on the downhill side
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Berm height should be same as the
uphill edge
Modify soil mix
Create overflow outlet
Mulch
Connect
Cross Section of a Rain Garden
Source: PGDER, 2002
•Ponding depth (4 to 9 inches)
•Mulch (2 to 4 inches)
•Modified soil mix depth (1 to 4 feet)
•Total depth ~2 to 4 feet
Ponding Depth
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A rain garden on a steeper slope will be deeper than a rain
garden on a flatter slope
Slope of 4% or less needs a 3 to 5” ponding depth
Slope of 5 - 7% needs a 6 to 7” ponding depth
Slope of 8 – 12% needs a 8 to 9” ponding depth
Be sure to account for mulch depth 2 to 4”
Measuring Slope
The Berm
Overflow Outlet
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Always have an overflow method for larger storms
 Lower area in the berm somewhere
 Stone weir, level spreader, overflow pipe
Modified Soil
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Depth: 1 to 4 feet (as deep as practicable)
3 - 4 inches of compost per foot of soil
 Aged compost with low level of N and P
 Soil Test
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http://www.etowahhcp.org/hcp_components.htm
2 to 4 inches of hardwood mulch
(no pine bark)
Connecting the
Rain Garden
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Direct water flow
Swale lined with
vegetation or rock
Buried drain pipe
Rain Garden Plants
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Aesthetic characteristics - variety
Theme Gardens
Variety of plant material
Tolerant of extremes
Right Plant, Right Place
http://www.bae.ncsu.edu/topic/raingarden/plants.htm
Maintenance
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Similar to other garden areas
Routine periodic landscaping
maintenance
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Weeding
Pruning
Replacing plants
Plant Division
Replacement of mulch
Questions?
Break (5 min)
Rainwater Harvesting
Benefits
Environmental Benefits
reduce erosion
reduce water use
Components of rain harvesting system:
 Collection
area
 Filtration
 Storage
 Delivery
and Distribution
Collection Area
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Draw house footprint
Divide roof into areas that go
to each gutter (delineate
catchments)
Measure each catchments
dimensions (length & width)
Calculate catchment area for
each gutter
Harvesting Potential for
1 inch rain
Square feet of roof
catchment area
50’ * 15’
750 ft2
Multiply by 0.623 gal/ft2
(converts ft2 to gallons per
inch of rain)
750 ft2 *0.623 gal/ft2
= 468 gallons
Monthly Rainfall (2007) Athens, GA
April
1.8 inches
May
0.55
June
2.23
July
3.04
August
1.31
September
2.15
October
1.61
November
2.12
Condensate from Air Conditioners
and Dehumidifiers
Home AC can produce over >5 gal./day
Condensate Harvesting Potential
AC production
Multiply by 7 to convert
to gallons per week
Multiply by 4 to
convert to gallons per
month
Example: 7 gal/day
49 gal. per week
~200 gal. per month
~7 gal/day yields ~200 gal/month
Filtration
Collection to Storage
Storage
Attractive
Cisterns
Make it Fun
Buried Tanks
- Septic tanks (baffles)
- More expensive
~$939/1000 gallon
$0.94/gallon
Sight Selection for Tanks
Maintenance
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Clean filters
Wash and clean out above ground barrels yearly
Keep roof gutters clean to minimize trash in
storage
Distribution –
Irrigating With Harvested Water
275 gallons
Distribution
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Pressurized
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Pumps and Electricity
Pump pressure
Non-pressurized
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Gravity flow
Use spigots and hose
Elevation
Pumps for Pressurized Systems
240 VAC
12VDC
Intake screen
Foot valve
Float Switches
Automation
Gravity Flow
Water Smart Irrigation
Components
Water
Application
System Maintenance
Backflow Preventer
•Prevents the irrigation system from
contaminating water supplies
Watts.com
Pressure Regulators
http://www.rainbird.com/drip/products/control/inline_reg.htm
Filter with Cleanout
Irrigation Filter
Micro Emitters
- Many shapes and styles
- Drip/bubbler emitters deliver 0.5 – 10
GPH
- Spray stakes deliver up to 45 GPH
- Very uniform water delivery
Other Emitters
Used to irrigate large uniform areas
High Impact
Stream Rotors
Irrigation Controller
Controllers and Operators
Rain Sensors
Soil Moisture
Sensors
Water savings of 46
to 88% reported in
Florida compared to
systems with just rain
sensors
(Lailhacar et al., 2005)
Irrigation Scheduling
• When are you allowed to irrigate?
What days?
What hours?
Don’t get fined
How long does the irrigation need to run?
1.Set out tuna cans randomly throughout
your lawn to collect water
2. Turn on irrigation 5 min.; check
to be sure irrigation is uniform;
adjust heads if irrigation isn’t
uniform
3. Average the water applied
and calculate how long to run
the system for the amount of
water your plants need
Example:
- 25 mature shrubs (4 feet tall)
- Plant requirement = 4 gallons each (1 gal/ft of ht)
- Total zone requirement: 25 x 4 = 100 gal/zone
Possible Setup:
- 2 GPH emitters & 2 per plant
- 4 GPH/plant, or 100 GPH/zone
This slow delivery rate decreases chance for runoff and a reason to promote micro-irrigation
techniques
Maintenance
Check for leaks
Water the plants,
not the pavement
Water Smart Landscapes
• Reduce sources of pollution
• Increase infiltration
• Enhance treatment/filtration
•Reduce consumption